#
# Copyright (c) 2017, Alliance for Open Media. All rights reserved
#
# This source code is subject to the terms of the BSD 2 Clause License and the
# Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License was
# not distributed with this source code in the LICENSE file, you can obtain it
# at https://www.aomedia.org/license/software-license. If the Alliance for Open Media Patent
# License 1.0 was not distributed with this source code in the PATENTS file, you
# can obtain it at https://www.aomedia.org/license/patent-license.
#

# Parses test/test-data.sha1 and writes captured file names and checksums to
# $out_files and $out_checksums as lists.
function(make_test_data_lists test_data_file out_files out_checksums)
    if(NOT test_data_file OR NOT EXISTS "${test_data_file}")
        message(FATAL_ERROR "Test info file missing or empty (${test_data_file})")
    endif()

    # Read $test_data_file into $files_and_checksums. $files_and_checksums becomes
    # a list with an entry for each line from $test_data_file.
    file(STRINGS "${test_data_file}" files_and_checksums)

    # Iterate over the list of lines and split it into $checksums and $filenames.
    foreach(line ${files_and_checksums})
        string(FIND "${line}" " *" delim_pos)

        math(EXPR filename_pos "${delim_pos} + 2")
        string(SUBSTRING "${line}" 0 ${delim_pos} checksum)
        string(SUBSTRING "${line}" ${filename_pos} -1 filename)

        # Include the name and checksum in output only when the file is needed.
        set(checksums ${checksums} ${checksum})
        set(filenames ${filenames} ${filename})
    endforeach()

    list(LENGTH filenames num_files)
    list(LENGTH checksums num_checksums)
    if(NOT checksums OR NOT filenames OR NOT num_files EQUAL num_checksums)
        message(FATAL_ERROR "Parsing of ${test_data_file} failed.")
    endif()

    set(${out_checksums} ${checksums} PARENT_SCOPE)
    set(${out_files} ${filenames} PARENT_SCOPE)
endfunction()

# Appends each file name in $test_files to $test_dir and adds the result path to
# $out_path_list.
function(expand_test_file_paths test_files test_dir out_path_list)
    foreach(filename ${${test_files}})
        set(path_list ${path_list} "${test_dir}/${filename}")
    endforeach()
    set(${out_path_list} ${path_list} PARENT_SCOPE)
endfunction()

function(check_file local_path expected_checksum out_needs_update)
    if(EXISTS "${local_path}")
        file(SHA1 "${local_path}" file_checksum)
    else()
        set(${out_needs_update} 1 PARENT_SCOPE)
        return()
    endif()

    if("${file_checksum}" STREQUAL "${expected_checksum}")
        unset(${out_needs_update} PARENT_SCOPE)
    else()
        set(${out_needs_update} 1 PARENT_SCOPE)
        return()
    endif()
    message("${local_path} up to date.")
endfunction()

# Downloads data from $file_url, confirms that $file_checksum matches, and
# writes it to $local_path.
function(download_test_file file_url file_checksum local_path)
    message("Downloading ${file_url} ...")
    file(DOWNLOAD "${file_url}" "${local_path}" SHOW_PROGRESS
        EXPECTED_HASH SHA1=${file_checksum})
    message("Download of ${file_url} complete.")
endfunction()
